Обсуждение: need substring based on delimiter
Hi:
I want to create a string from the first 3 elements of a csv (for example). The csv is longer than 3 elements. Example...
aaa,bbb,ccc,ddd,eee,fff,ggg
I want the string "aaa,bbb,ccc".
Tried splitting this to an array (precursor to appending elements 1,2,3), but failed to be able to reference the elements returned...
stdb_a0=# select string_to_array('aaa,bbb,ccc,ddd,eee,fff,ggg',',');
string_to_array
-------------------------------
{aaa,bbb,ccc,ddd,eee,fff,ggg}
(1 row)
stdb_a0=# select string_to_array('aaa,bbb,ccc,ddd,eee,fff,ggg',',')[1];
ERROR: syntax error at or near "["
If there was a way "position" would return the pos of the 3rd comma, I could use sustring. But I don't think it can :-(
On 08/23/2012 02:30 PM, Gauthier, Dave wrote: > I want to create a string from the first 3 elements of a csv (for > example). The csv is longer than 3 elements. Example... > > aaa,bbb,ccc,ddd,eee,fff,ggg > > I want the string "aaa,bbb,ccc". select array_to_string ( ( string_to_array ( 'aaa,bbb,ccc,ddd,eee,fff,ggg',',' ) )[1:3],',' ); array_to_string ----------------- aaa,bbb,ccc (1 row) HTH, Joe -- Joe Conway credativ LLC: http://www.credativ.us Linux, PostgreSQL, and general Open Source Training, Service, Consulting, & 24x7 Support